[libvirt] [PATCH v3 3/7] lib: introduce virDomainGetStateParams function

[Daniel P. Berrangé]

On Thu, Apr 04, 2019 at 10:01:30AM +0200, Bjoern Walk wrote:
> This API function extends the virDomainGetState function by returning
> additional state information as a dictionary of typed parameters.
> 
> Reviewed-by: Boris Fiuczynski <fiuczy at linux.ibm.com>
> Signed-off-by: Bjoern Walk <bwalk at linux.ibm.com>
> ---
>  include/libvirt/libvirt-domain.h | 76 ++++++++++++++++++++++++++++++++
>  src/driver-hypervisor.h          |  9 ++++
>  src/libvirt-domain.c             | 62 ++++++++++++++++++++++++++
>  src/libvirt_public.syms          |  5 +++
>  4 files changed, 152 insertions(+)
> +/**
> + * virDomainGetStateParams:
> + * @domain: a domain object
> + * @state: returned state of the domain (one of virDomainState)
> + * @reason: returned reason which led to @state (one of virDomain*Reason)
> + * @params: where to store additional state information, must be freed by
> + *          the caller
> + * @nparams: number of items in @params
> + * @flags: bitwise-OR of virDomainGetStateFlags,
> + *         not currently used yet, callers should always pass 0
> + *
> + * Extract domain state. Each state is accompanied by a reason (if known)
> + * and optional detailed information.
> + *
> + * Possible fields returned in @params are defined by VIR_DOMAIN_STATE_PARAMS_*
> + * macros and new fields will likely be introduced in the future so callers
> + * may receive fields that they do not understand in case they talk to a newer
> + * server. The caller is responsible to free allocated memory returned in
> + * @params by calling virTypedParamsFree.
> + *
> + * Returns 0 in case of success and -1 in case of failure.
> + */
> +int
> +virDomainGetStateParams(virDomainPtr domain,
> +                        int *state,
> +                        int *reason,
> +                        virTypedParameterPtr *params,
> +                        int *nparams,
> +                        unsigned int flags)
> +{
> +    virConnectPtr conn = domain->conn;
> +
> +    VIR_DOMAIN_DEBUG(domain, "params=%p, nparams=%p, flags=0x%x",
> +                     params, nparams, flags);
> +
> +    virResetLastError();
> +
> +    virCheckDomainReturn(domain, -1);
> +    if (params)
> +        virCheckNonNullArgGoto(nparams, error);

While I remember, we must forbid this for "read only" connections, as
some of the parameters are CPU registers which may hold sensitive data.

> +
> +    if (VIR_DRV_SUPPORTS_FEATURE(conn->driver, conn,
> +                                 VIR_DRV_FEATURE_TYPED_PARAM_STRING))
> +        flags |= VIR_TYPED_PARAM_STRING_OKAY;
> +
> +    if (conn->driver->domainGetStateParams) {
> +        int ret;
> +        ret = conn->driver->domainGetStateParams(domain, state, reason,
> +                                                 params, nparams, flags);
> +        if (ret < 0)
> +            goto error;
> +        return ret;
> +    }
> +
> +    virReportUnsupportedError();
> +
> + error:
> +    virDispatchError(domain->conn);
> +    return -1;
> +}
> +

Regards,
Daniel
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